1. Field of the Invention
This invention is directed to a semiconductor structure that includes a dual gate structure for use as a radio frequency mixer and switch.
2. Description of the Related Art
A means of switching radio frequency (rf) energy is important for on-chip radio applications. Desired characteristics of a radio frequency switch include low loss, high isolation, large dynamic range, and low distortion. As transistor design is improved and evolves, the number of different types of transistors continues to increase. For example, one type of transistor that uses a fin-shaped channel region covered with a gate conductor, with the outer portions of the fin being used as source/drain regions, is referred to as a fin-type field effect transistor (FinFET). One such FinFET is disclosed in U.S. Pat. No. 6,413,802 to Hu et al. (hereinafter “Hu”) and the disclosure of the same is incorporated herein by reference. A dual gate version of a FinFET device is disclosed in US patent publication number 20030111686, which is incorporated herein by reference. Another type of transistor that has been developed recently is a dual gate metal oxide semiconductor (MOS) transistor such as that disclosed in US patent publication number 20040235283, which is also incorporated herein by reference. It would be advantageous to utilize this evolving transistor technology in the field of radio frequency devices, and the invention described below is directed to such advantages.